The present invention relates to a device for collecting and selecting embryos of a domestic animal such as cow. More particularly, it relates to a device for separating ova from a perfusate containing them, which is drawn from the uterus of an animal, by filtration, and selecting embryos by discriminating useful ova (normal embryo) from unuseful ova (nonfertilized ovum, too young embryo, abnormal embryo) through a magnifier.
Heretofore, selection of embryos in artificial insemination of domestic animal, particularly cow, has been carried out by using a device as shown in FIG. 5. A perfusate containing embryos which is drawn from the uterus of a cow is filtered by using an embryo-collecting device 10 having a metal mesh filter 11 provided at the bottom thereof. When the liquid level within the device 10 goes down to a height of 10 to 20 mm above the filter 11, the filtration is stopped by cramping a tube 13 connected to an outlet 12 of the device 10 by means of a cramp 14. The embryos attached to the filter 11 are removed by means of a pipette or the like. Thus obtained liquid containing embryos is transferred to a Petri dish or the like. The embryos were selected on the dish with being observed through a magnifier.
However, the above-mentioned conventional method has the following drawbacks. A liquid containing embryos obtained in the embryo-collecting device 10 must be transferred to another device such as Petri dish for selecting embryos. Some of the embryos attached to the filter are apt to remain as they are after the removal operation using a pipette or the like is conducted. In order to avoid the remaining of embryos, generally, the removal operation and subsequent transfer operation are repeated three times, which are troublesome and require to prepare additional embryo-selecting dishes. Further, there is a danger that embryos are lost when they are transferred from the embryo-collecting device to the embryo-selecting dish.
It is an object of the present invention to provide a simple and cheap device for collecting and selecting embryos by which both the filtration of a perfusate containing embryos and the selection of embryos can be effected without any operation for transferring a liquid containing embryos to another device.
This and other objects of the invention will become apparent from the description hereinafter.